NetBSD/usr.sbin/sup/source/setproctitle.c

115 lines
3.0 KiB
C

/*-
* Copyright (c) 2007 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/param.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <limits.h>
#include <unistd.h>
#ifdef NEED_SETPROCTITLE
extern char **__environ;
void
setproctitle(const char *fmt, ...)
{
va_list ap;
char buf[1024];
int len;
char *pname, *p, *s;
/*
* Assumes that stack grows down, and than environ has not bee
* reallocated because of setenv() required growth. Stack layout:
*
* argc
* argv[0]
* ...
* argv[n]
* NULL
* environ[0]
* ...
* environ[n]
* NULL
*/
/* 1 for the first entry, 1 for the NULL */
char **args = __environ - 2, *s;
#ifdef _SC_ARG_MAX
s = (char *)sysconf(_SC_ARG_MAX);
#elifdef ARG_MAX
s = (char *)ARG_MAX;
#elifdef NCARGS
s = (char *)NCARGS;
#else
s = (char *)(256 * 1024);
#endif
/*
* Keep going while it looks like a pointer. We'll stop at argc,
* Which is a lot smaller than a pointer, limited by ARG_MAX
*/
while (*args > s)
args--;
*(int *)args = 1; /* *argc = 1; */
pname = *++args; /* pname = argv[0] */
/* Just the last component of the name */
if ((p = strrchr(pname, '/')) != NULL)
pname = p + 1;
/* In case we get called again */
if ((p = strrchr(pname, ':')) != NULL)
*p = '\0';
va_start(ap, fmt);
if (fmt != NULL) {
len = snprintf(buf, sizeof(buf), "%s: ", pname);
if (len >= 0)
(void)vsnprintf(buf + len, sizeof(buf) - len, fmt, ap);
} else
(void)snprintf(buf, sizeof(buf), "%s", pname);
va_end(ap);
(void)strcpy(pname, buf);
}
#endif
#ifdef TEST
int
main(int argc, char **argv)
{
setproctitle("foo");
sleep(1000);
return 0;
}
#endif